1. Technical Field
The present invention relates to a toner for developing electrostatic charge image.
2. Description of Related Art
In recent years, a decrease in thermal energy at the time of fixing a toner image has been desired for the purpose of increasing the printing speed, decreasing the environmental burden, and the like.
A technique is desired which can improve the low temperature fixability of the toner in order to decrease such thermal energy at the time of fixing the toner image, and as one of the means to achieve it, there is a method to use a crystalline resin exhibiting excellent sharp melting property such as a crystalline polyester in the binder resin. In addition, a toner for developing an electrostatic charge image, which contains a binder resin containing a crystalline polyester resin and an amorphous resin, is proposed as a toner exhibiting superior low temperature fixability. In this manner, it is possible to achieve low temperature fixation as the crystalline portion is melted when the temperature exceeds the melting point of the crystalline polyester by the temperature history at the time of fixing and the crystalline polyester resin and the amorphous resin are compatibilized with each other by using a mixture of a crystalline polyester resin and an amorphous resin.
For example, Japanese Patent Application Laid-Open No. 2012-226296 discloses an image forming method to use a toner for developing an electrostatic charge image which contains at least a binder resin containing a crystalline polyester and an amorphous polyester, a colorant, and a releasing agent is disclosed. In addition, Japanese Patent Application Laid-Open No. 2014-74882 discloses a toner containing at least a binder resin and a colorant, in which the binder resin contains a crystalline polyester resin (A), an amorphous resin (B), and a composite resin (C) containing a condensation polymerization-based resin unit and an addition polymerization-based resin unit. Furthermore, Japanese Patent Application Laid-Open No. 2012-255957 discloses a toner for developing an electrostatic charge image having a core-shell structure which has core particles formed to contain at least a binder resin and wax and a shell layer formed to coat the core particle, in which the binder resin contains at least a crystalline polyester resin and a styrene-acrylic resin. In addition, Japanese Patent Application Laid-Open No. 2011-53494 discloses a binder resin for electrophotographic toner, in which the binder resin is composed of a resin obtained by subjecting an aqueous dispersion containing a crystalline resin and an aqueous dispersion containing an amorphous resin to an aggregation step and a coalescence step and in which the crystalline resin is a composite resin containing a condensation polymerization-based resin component obtained through condensation polymerization of an alcohol component containing an aliphatic diol having from 2 to 10 carbon atoms and a carboxylic acid component and a styrene-based resin component.